Water Pressure Puzzel - SailNet Community

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  #1  
Old 05-31-2010
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Water Pressure Puzzel

I'm assuming (I know what they say about that) that I have a fresh water pressure leak because my pump keeps cycling every few minutes. I replaced 90% of my fresh water hose last summer and rechecked all the connections - no leaks found. I can't find any water leaks anywhere, I've doubled checked this. I removed the accumulator tank from the system and still have pump cycling. I've inspected the pump with no type of leaks detected. This all started after I put new faucet washers in the head. I did shut off the water and for this repair but afterwards I reprimed the lines with no problem and the water runs fine with no air spurting out. Another curious thing is that everytime the pump cycles, the manual pump faucets spit out a little water. Now this was happening berfore the constant pump cycling so I don't thing it's the problem, but is that common? I don't know what else to check.
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Old 05-31-2010
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put the accumulator back in it will help with the cycling, ie it wont happen as often. as for the cycling it does not take much leakage back thru the pump to make it cycle again. with out a accumulator it can cycle if as little as a 1/8 cup or so leaks back, as soon as the pressure drops it will run again and with no accumulator only the hoses swelling under pressure keep the pressure up. if it bugs you that much a check valve between the tank and pump will help. i turn my pump off if i wont be using water in the next hour
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Old 05-31-2010
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Quote:
Originally Posted by cvsheppard View Post
I'm assuming (I know what they say about that) that I have a fresh water pressure leak because my pump keeps cycling every few minutes. I replaced 90% of my fresh water hose last summer and rechecked all the connections - no leaks found. I can't find any water leaks anywhere, I've doubled checked this. I removed the accumulator tank from the system and still have pump cycling. I've inspected the pump with no type of leaks detected. This all started after I put new faucet washers in the head. I did shut off the water and for this repair but afterwards I reprimed the lines with no problem and the water runs fine with no air spurting out. Another curious thing is that everytime the pump cycles, the manual pump faucets spit out a little water. Now this was happening berfore the constant pump cycling so I don't thing it's the problem, but is that common? I don't know what else to check.
Carl,

Try reinstalling the accumulator tank. Its purpose is to prevent the constant cycling that you are describing. The pressure bladder in the tank will maintain constant pressure against the switch for a much longer period than your water lines will.

There is likely a leak somewhere in your system. If you aren't discovering water outside of the system, it could be internal to the pump.
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Old 05-31-2010
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I would guess that it's bleeding back through the pump. You could check this by disconnecting the hose on the pressure side of the pump and attaching a short length of hose with a plug or a bolt hose clamped in the end. Start the pump and if there are no leaks and it cycles you know it's going back thru the pump. Depending on the type of pump you might be able to rebuild it.
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Old 05-31-2010
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I'd add a check valve AFTER the pump in the pressure side, not in the suction. Generally check valves in the suction are a bad idea. Putting it after the pump, and assuming the pump is leaking back, will actually make it easier for the pump to start up.

Gary H. Lucas
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in some ways gary you are right, the check valve after the pump will let the motor start easier if it leaks down. the problem with this is now you only have a few inches of hose to hold pressure, unless the accumulator is before the valve, but that means it can still leak down
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Old 05-31-2010
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If you have a water heater hooked up, check the WH for leaks. I had one that was leaking through the heating element.
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Thanks everyone for you input. Turns out jrd22 was right, it was the pump. Replaced pump and all is right again in the world, for a few minutes. I still get some water discharge from the manual faucet whenever I use the pressure system. Is that normal?
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Old 05-31-2010
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I don't know if it is "normal" or not, but mine does the same thing - sometimes. Glad you figured out what was going on.
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yes it is normal, look at it like this.

the manual pump is nothing but 2 check valves, one allows water into the "pump" the other allows it out. ie both valve go the same way tank to the sink, when the pressure changes the valves leak a little. when the pressure stabilizes the valves seal using the spring in them. if the manual pump was new it might not leak, notice i said might

edit

you might want to run a new water line for the manual pump straight to the tank. that way if the 12v pump dies you are not trying to pull water thru the 12 v pump. this will stop the leak, and allow you to just pump a little water manually when needed without turning on the 12 v pump

Last edited by scottyt; 05-31-2010 at 09:58 PM.
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